Aromatization of 7α-Methyl-19-nortestosterone by human placental microsomes in vitro

@article{LaMorte1994AromatizationO7,
  title={Aromatization of 7$\alpha$-Methyl-19-nortestosterone by human placental microsomes in vitro
},
  author={A. LaMorte and Narender Kumar and C. Bardin and K. Sundaram},
  journal={The Journal of Steroid Biochemistry and Molecular Biology},
  year={1994},
  volume={48},
  pages={297-304}
}
Abstract Part of the biological effects of testosterone (T) are mediated by its enzymatic reduction to 5α-dihydrotestosterone (DHT) or aromatization to estradiol (E 2 ). 7α-Methyl-19-nortestosterone (MENT) is a synthetic androgen that is considerably more potent than T. Previous studies have shown that MENT is not 5α-reduced. The studies reported here were undertaken to determine whether MENT undergoes enzymatic aromatization in vitro . Human placental microsomes were used as the source of the… Expand
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The results suggest that the addition of 19-nortestosterone-derived progestins, as a hormonal adjuvant in male fertility strategies for effective spermatogenic suppression, does not display any detrimental effect that would interfere with MENT androgenic transcriptional activity. Expand
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TLDR
The results demonstrate for the first time in humans the selectivity of MENT in tissues dependent on 5 alpha-reductase and are consistent with the importance of adequate estrogenicity as part of the necessary spectrum of activity of an androgen for replacement therapy in men. Expand
Formation of 7&agr;-methyl-ethinyl estradiol during treatment with tibolone
TLDR
Investigation of whether tibolone, which is orally used for hormone replacement therapy, is transformed to a derivative of ethinyl estradiol (EE), demonstrates that, during daily treatment of women with 2.5 mg tiblone, a small proportion of tIBolone is transformation to 7&agr;-methyl-EE. Expand
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